Improvement in the manufacture of pyroligneous acid



NITED; STATES PATENT OFFIca,

A. H. EMERY,OF NEW YORK, N. Y.

Specification forming part of Letters Patent No. 49,247, dated August 8;1865.

To all whom it may concern;

Be it known that I, A. H. EMERY, of the city, county and State of NewYork, have invented a new and Improved Process of Manufacturin gPyroligneous Acid, &c., from Pine Wood; and I do hereby declare that thefollowing is a full and exact description thereof.

The nature of my invention consists in the method of using steam in themanufacture of pyroligneons acid, 850., from pine wood, where I use thesteam in such quantities and at'such times as to produce the bestresults.

To enable others skilled in the art to make use of my invention, I willproceed to describe the precise operation.

In the manufacture of pyroligneous acid from wood heretofore, wheneither steam or superheated steam has been used, it has been customaryto let a continuous and nearly constant supply of steam through theretort or still in which the wood is being distilled irtitil the wood ischarred, the temperature of the still or retort being raisedsufficiently to destroy the wood as quickly as is practical afterdistillation commences, andin this case all the steam serves to dilutethe acid.

The proper way to use the steam, and the Way I use it, is to let thesteam on the wood in large quantities at first, which heats it up anddries it rapidly, while the heat is not raised sufficiently to destroyand char the wood. This process is continued until the wood isthoroughly dried and a large portion of the spirits of turpentine androsin taken out; at

ter which the heat is raised up sufiiciently to commence the rapidcharring, when the acid is rapidly formed, the steam being nearly orquite shut off. Ofcourse a small amount might still be let in withoutmaterially modifying the results, and if much is used the acid ismaterially injured, with no corresponding gain in the value of the otherproducts.

I do not claim the use of steam in the distillation of wood; but

What I do here claim, and desire to secure by' Letters Patent, is-

The use of steam or superheated steam in the distillation of wood in themanufacture of pyroligenous acid, &c., in those casesin which the amountof steam used is greatly decreased or discontinued during the Whole ofor a large portion of the timein which the wood is being charred.

A. H. EME RY.

Witnesses e W, A. CRAWFORD, C. F. EMERY.

